CN103712959A - Cambered surface electrode discharging-based laser-induced breakdown spectroscopy detection system - Google Patents
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- CN103712959A CN103712959A CN201310611350.7A CN201310611350A CN103712959A CN 103712959 A CN103712959 A CN 103712959A CN 201310611350 A CN201310611350 A CN 201310611350A CN 103712959 A CN103712959 A CN 103712959A
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Abstract
The invention discloses a cambered surface electrode discharging-based laser-induced breakdown spectroscopy detection system and belongs to the field of laser-induced breakdown spectroscopy. The cambered surface electrode discharging-based laser-induced breakdown spectroscopy detection system is characterized in that a cambered surface electrode discharging device is used based on the conventional laser-induced breakdown spectroscopy system. The cambered surface electrode discharging device comprises a high voltage supply, a capacitance, a high voltage cable, an insulating layer and two cambered surface electrodes. Through electrode discharging, a large amount of electric energy is poured into laser-induced plasmas so that a spectral signal is improved obviously, a cylindrical cavity formed from the cambered surfaces and insulating layers of the cambered surface electrodes can restrain a plasma spatial form, and a plasma temperature and electron density are improved and thus the spectral signal has larger intensity and better stability. The cambered surface electrode discharging-based laser-induced breakdown spectroscopy detection system is simple and reliable and has a low cost and good practicality.
Description
Technical field
The present invention relates to Laser-induced Breakdown Spectroscopy detection system, particularly a kind of Laser-induced Breakdown Spectroscopy detection system of improving spectral signal quality based on cambered surface electrode discharge, belongs to Laser-induced Breakdown Spectroscopy technical field.
Background technology
Laser-induced Breakdown Spectroscopy (laser-induced breakdown spectroscopy, LIBS) is a kind of brand-new material element analytical technology growing up in the twentieth century later stage, is a kind of typical atomic emission spectrum measuring technique.The principle of work of LIBS is: under intense laser pulse effect, the material of sample surfaces is provoked into as plasma decay rapidly, in attenuation process, give off the photon of characteristic frequency, produce characteristic spectral line, element kind and concentration information that its frequency and strength information have comprised analytic target.LIBS technical operation cost is low, and measuring speed is fast, have high sensitivity, without or need sample pretreatment seldom and realize the advantages such as multielement measurement, and radiationless harm has great development potentiality in commercial production.
But in actual applications,, LIBS detects and to have that sensitivity is lower, detectability is not enough and the repeated poor shortcoming of signal, thereby has limited the widespread use of this technology.In order to promote the development of LIBS technology, strengthening signal intensity, improving detectability, improve signal repeatability is the important research direction of LIBS technology.
In order to improve the intensity of LIBS signal, some researchers have proposed the method that spark discharge strengthens signal (as application number: 201120391281.X patent documentation; Application number: 200910154015.2 patent documentations, application number: 201110311616.7 patent documentations, application number: 200920199159.5 patent documentations).These methods by electric arc electric energy injected plasma, can obviously increase the intensity of LIBS signal, but because the electric arc of discharge generation is very unstable, and the effective machining area of sphere pole adopting is very little, cause signal stabilization deficiency and enhancement effect insufficient, the relative position of two electrodes need to be fixed respectively simultaneously, to practical operation, has brought inconvenience.
Summary of the invention
The deficiency and the defect that for prior art, exist, the present invention proposes a kind of Laser-induced Breakdown Spectroscopy detection system based on cambered surface electrode discharge, further to strengthen signal intensity, improve detectability and to improve signal repeatability, thereby LIBS technology is used widely.
Technical scheme of the present invention is as follows:
A kind of Laser-induced Breakdown Spectroscopy detection system based on cambered surface electrode discharge, this system comprises pulsed laser, condenser lens, probe, optical fiber, spectrometer and computing machine, it is characterized in that: described system also comprises cambered surface electrode discharge device, cambered surface electrode discharge device is placed on testing sample surface, and described cambered surface electrode discharge device comprises the positive pole of high-voltage DC power supply, electric capacity, high-tension cable, insulation course, cambered surface electrode and the negative pole of cambered surface electrode; High-voltage DC power supply is in parallel by high-tension cable with electric capacity, the negative pole of the positive pole of cambered surface electrode and cambered surface electrode is connected with negative pole with the positive pole of high-voltage DC power supply by high-tension cable respectively, and described insulation course is between the positive pole of cambered surface electrode and the negative pole of cambered surface electrode; Between the negative pole of the positive pole of cambered surface electrode, cambered surface electrode and insulation course, form a cylindrical cavity; The pulse laser that pulsed laser sends center through cylindrical cavity after condenser lens focuses on impacts at the surface of testing sample generation plasma, the light signal that plasma sends is after probe, optical fiber and spectrometer are collected, light signal is converted to electric signal input computing machine, obtains the spectral signal of testing sample.
The material of described cambered surface electrode anode and cambered surface electrode negative pole is cerium tungsten alloy.
The degree of depth of described cylindrical cavity is 1mm～15mm, and diameter is 1mm～15mm.
The present invention has the following advantages and high-lighting effect: effective machining area of cambered surface electrode is much larger than sphere pole and can produce electric arc in plasma surrounding, thereby can the electric energy of storing in electric capacity be injected in plasma fully, the enhancement effect of spectral signal is more obvious, is conducive to improve the detectability that LIBS measures; Simultaneously owing to can plasma surrounding discharging, the electric arc producing is more stable, be conducive to improve the stability of spectral signal, and the shock wave of following in plasma generation process is acted on plasma by after the inwall of cylindrical cavity reflection, the energy that shock wave carries is on the one hand enhanced spectrum signal further, also effect of contraction has been played in the spatial shape of plasma and position on the other hand, the impact of the fluctuation of having avoided plasma space form and position on signal stabilization, is conducive to improve the stability of spectral signal.
Accompanying drawing explanation
Fig. 1 is the Laser-induced Breakdown Spectroscopy system diagram based on cambered surface electrode discharge.
Fig. 2 is cambered surface electrode discharge device structural drawing.
In figure: the positive pole of 1-cambered surface electrode; 2-insulation course; 3-cylindrical cavity; The negative pole of 4-cambered surface electrode; 5-high-voltage DC power supply; 6-electric capacity; 7-high-tension cable; 8-pulsed laser; 9-condenser lens; 10-plasma; 11-cambered surface electrode discharge device; 12-testing sample; 13-probe; 14-optical fiber; 15-spectrometer; 16-computing machine.
Embodiment
Below in conjunction with accompanying drawing, the present invention is further illustrated.
Fig. 1 is the Laser-induced Breakdown Spectroscopy system diagram based on cambered surface electrode discharge, and this system comprises pulsed laser 8, condenser lens 9, cambered surface electrode discharge device 11, probe 13, optical fiber 14, spectrometer 15 and computing machine 16; Described cambered surface electrode discharge device 11 is placed on testing sample surface, and this device comprises the positive pole 1 of high-voltage DC power supply 5, electric capacity 6, high-tension cable 7, insulation course 2, cambered surface electrode and the negative pole 4 of cambered surface electrode; High-voltage DC power supply is in parallel by high-tension cable with electric capacity, the negative pole of the positive pole of cambered surface electrode and cambered surface electrode is connected with negative pole with the positive pole of high-voltage DC power supply by high-tension cable respectively, and described insulation course 2 is between the positive pole of cambered surface electrode and the negative pole of cambered surface electrode; Between the negative pole of the positive pole of cambered surface electrode, cambered surface electrode and insulation course, form a cylindrical cavity 3(as shown in Figure 2); The pulse laser that pulsed laser sends center through cylindrical cavity 3 after condenser lens focuses on impacts at the surface of testing sample 12 generation plasma 10, the light signal that plasma sends is after probe, optical fiber and spectrometer are collected, light signal is converted to electric signal input computing machine, obtains the spectral signal of testing sample.The material of described cambered surface electrode anode and cambered surface electrode negative pole adopts cerium tungsten alloy; Distance between the positive pole 1 of cambered surface electrode and the negative pole 4 of cambered surface electrode is that the width of insulation course 2 is D, and the size of D is preferably 1mm～15mm; The diameter of cylindrical cavity 3 is Φ, and the size of Φ is preferably 1mm～15mm; The degree of depth of cylindrical cavity is that the thickness of cambered surface electrode is H, and H size is 1mm～15mm; The voltage of high-voltage DC power supply is generally 3kV-15kV, and capacitance size is generally 5nF-10 μ F.
Principle of work of the present invention and process are as follows:
Effective machining area of cambered surface electrode is much larger than sphere pole and can produce electric arc in plasma surrounding, thereby can the electric energy of storing in electric capacity be injected in plasma fully, the enhancement effect of spectral signal is more obvious, be conducive to improve signal to noise ratio (S/N ratio) and the detectability that LIBS measures, simultaneously owing to can plasma surrounding discharging, the electric arc producing is more stable, is conducive to improve the stability of spectral signal; And the shock wave of following in plasma generation process is acted on plasma by after the inwall of cylindrical cavity reflection, the energy that shock wave carries is on the one hand enhanced spectrum signal further, also effect of contraction has been played in the spatial shape of plasma and position on the other hand, the impact of the fluctuation of having avoided plasma space form and position on signal stabilization, is conducive to improve the stability of spectral signal.
The discharge process of described cambered surface electrode is passive, without manual control.When laser pulse does not send, in the middle of the cylindrical cavity that cambered surface electrode and insulation course form, there is free air bound exhausted, two electrodes cannot be discharged.When the center of laser pulse through cylindrical cavity impacts after sample surfaces, sample surfaces produces plasma, the resistance in cylindrical cavity is reduced greatly, two electrode transient switchings, produce arc discharge, thereby store electrical energy injected plasma in electric capacity.
The process of using device of the present invention to detect testing sample is as follows:
Pulsed laser sends beam of laser pulse, and laser pulse impacts on testing sample surface through the cylindrical cavity of cambered surface electrode and insulation course formation after condenser lens focuses on, and produces laser induced plasma.In the cylindrical cavity of plasma between two cambered surface electrodes, ion in plasma and electronics reduce two resistance moments between electrode, thereby two electrode conductions, form the electric energy of storing in electric capacity by arc discharge is injected in plasma, causes atom, ion in plasma further fully to be excited.The optical radiation that the atom of excited state and ion send enters probe, after entering spectrometer by optical fiber, be converted into electric signal, electric signal can be obtained the spectrum of testing sample by computer acquisition, and the element that can obtain testing sample by analyzing spectral characteristic forms information.
Embodiment:
The standard coal sample ZBM098 of take is example, contrasts the spectral signal that conventional LIBS, sphere pole strengthen the carbon that LIBS, tri-kinds of technology of cambered surface electrode discharge LIBS of the present invention obtain.Before experiment, coal sample is pressed into briquette as testing sample with sheeter.
Adopt ND:YAG pulsed laser, optical maser wavelength is 532nm, and laser energy is set to 35mJ, and the focal length of condenser lens is 20cm, and focus is positioned at the following 4mm in testing sample surface.Spectrometer starts collection signal after 1 μ s after laser pulse sends.The diameter of phi of cylindrical cavity is 3mm, and depth H is 1.5mm.The voltage of high-voltage DC power supply is set to 7.5kV, and capacitance size is 20nF.The sphere pole diameter that is used for contrasting is 3mm, and the spacing between two electrodes is 3mm, and electrode is at the above 1.5mm of sample surfaces.20 diverse locations at sample surfaces gather 20 width spectral signals, try to achieve average strength and the relative standard deviation (RSD) of carbon spectral line C (I) 193.09nm, and signal to noise ratio snr, and plasma temperature and electron density are as shown in table 1.
The spectral characteristic contrast of table 1 different technologies scheme
As shown in Table 1, utilize the LIBS spectrum of the cambered surface electrode discharge device gained that the present invention proposes, than conventional LIBS and globular discharge LIBS, there is stronger signal intensity, larger signal to noise ratio (S/N ratio), higher plasma temperature and electron density, therefore can improve the detectability that LIBS measures, meanwhile, utilize cambered surface electrode discharge device that the present invention proposes can greatly reduce the RSD of signal, can improve the stability of signal.Generally speaking, cambered surface electrode discharge device provided by the invention, simple to operate, with low cost, can greatly strengthen signal intensity, improve detectability and signal stabilization.
Claims (3)
1. the Laser-induced Breakdown Spectroscopy detection system based on cambered surface electrode discharge, this system comprises pulsed laser (8), condenser lens (9), probe (13), optical fiber (14), spectrometer (15) and computing machine (16), it is characterized in that: described system also comprises cambered surface electrode discharge device (11), cambered surface electrode discharge device (11) is placed on testing sample surface, described cambered surface electrode discharge device comprises high-voltage DC power supply (5), electric capacity (6), high-tension cable (7), insulation course (2), the negative pole (4) of the positive pole of cambered surface electrode (1) and cambered surface electrode, high-voltage DC power supply is in parallel by high-tension cable with electric capacity, the negative pole of the positive pole of cambered surface electrode and cambered surface electrode is connected with negative pole with the positive pole of high-voltage DC power supply by high-tension cable respectively, and described insulation course (2) is between the positive pole of cambered surface electrode and the negative pole of cambered surface electrode, between the negative pole of the positive pole of cambered surface electrode, cambered surface electrode and insulation course, form a cylindrical cavity (3), the pulse laser that pulsed laser sends center through cylindrical cavity (3) after condenser lens focuses on impacts at the surface of testing sample (12) generation plasma (10), the light signal that plasma sends is after probe, optical fiber and spectrometer are collected, light signal is converted to electric signal input computing machine, obtains the spectral signal of testing sample.
2. a kind of Laser-induced Breakdown Spectroscopy detection system based on cambered surface electrode discharge according to claim 1, is characterized in that: the material of described cambered surface electrode anode and cambered surface electrode negative pole adopts cerium tungsten alloy.
3. a kind of Laser-induced Breakdown Spectroscopy detection system based on cambered surface electrode discharge according to claim 1, is further characterized in that: the degree of depth of cylindrical cavity is 1mm～15mm, and diameter is 1mm～15mm.
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105699359A (en) * | 2016-01-18 | 2016-06-22 | 大连理工大学 | Experimental device and method for obtaining annular uniform plasmas in barometric pressure air |
| CN106644407A (en) * | 2016-12-13 | 2017-05-10 | 西南技术物理研究所 | Laser-induced plasma ignition time measurement device |
| CN107884128A (en) * | 2017-10-24 | 2018-04-06 | 中国航天空气动力技术研究院 | A kind of electro-arc heater water leakage fault diagnostic system based on atomic emission spectrum |
| CN108459012A (en) * | 2017-12-28 | 2018-08-28 | 中国科学院合肥物质科学研究院 | Portable laser plasma spark electric discharge component spectrum detecting system |
| CN112255149A (en) * | 2020-10-10 | 2021-01-22 | 中国科学院近代物理研究所 | Method and system for detecting particle size of loose particle accumulation and storage medium |
| CN113310968A (en) * | 2021-04-22 | 2021-08-27 | 清华大学 | Method for improving repeatability of laser-induced breakdown spectroscopy based on beam shaping |
| CN114062348A (en) * | 2021-11-22 | 2022-02-18 | 清华大学 | Laser-induced breakdown spectroscopy detection system based on dielectric barrier discharge |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2620805B2 (en) * | 1987-06-04 | 1997-06-18 | ソルテック・ゲーエムベーハー | Metal Scrap Analysis Method and Apparatus |
| US5847825A (en) * | 1996-09-25 | 1998-12-08 | Board Of Regents University Of Nebraska Lincoln | Apparatus and method for detection and concentration measurement of trace metals using laser induced breakdown spectroscopy |
| US7692789B1 (en) * | 2007-04-13 | 2010-04-06 | The United States Of America As Represented By The United States Department Of Energy | High resolution analysis of soil elements with laser-induced breakdown |
| CN101696936A (en) * | 2009-10-22 | 2010-04-21 | 浙江师范大学 | Laser induced discharge reinforcement plasma spectrum detection device |
| WO2012109892A1 (en) * | 2011-02-18 | 2012-08-23 | 清华大学 | Method and system for improving precision of element measurement based on laser-induced breakdown spectroscopy |
| CN203587500U (en) * | 2013-11-26 | 2014-05-07 | 清华大学 | Cambered surface electrode discharging-based laser-induced breakdown spectrum detecting system |
-
2013
- 2013-11-26 CN CN201310611350.7A patent/CN103712959B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2620805B2 (en) * | 1987-06-04 | 1997-06-18 | ソルテック・ゲーエムベーハー | Metal Scrap Analysis Method and Apparatus |
| US5847825A (en) * | 1996-09-25 | 1998-12-08 | Board Of Regents University Of Nebraska Lincoln | Apparatus and method for detection and concentration measurement of trace metals using laser induced breakdown spectroscopy |
| US7692789B1 (en) * | 2007-04-13 | 2010-04-06 | The United States Of America As Represented By The United States Department Of Energy | High resolution analysis of soil elements with laser-induced breakdown |
| CN101696936A (en) * | 2009-10-22 | 2010-04-21 | 浙江师范大学 | Laser induced discharge reinforcement plasma spectrum detection device |
| WO2012109892A1 (en) * | 2011-02-18 | 2012-08-23 | 清华大学 | Method and system for improving precision of element measurement based on laser-induced breakdown spectroscopy |
| CN203587500U (en) * | 2013-11-26 | 2014-05-07 | 清华大学 | Cambered surface electrode discharging-based laser-induced breakdown spectrum detecting system |
Non-Patent Citations (4)
| Title |
|---|
| K. A. TERESZCHUK ET AL.: "Glow-Discharge-Assisted Laser-Induced Breakdown Spectroscopy: Increased Sensitivity in Solid Analysis", 《APPLIED SPECTROSCOPY》 * |
| LEON RADZIEMSKI ET AL.: "A brief history of laser-induced breakdown spectroscopy: From the concept of atoms to LIBS 2012", 《SPECTROCHIMICA ACTA PART B》 * |
| O. AYED NASSEF ET AL.: "Spark discharge assisted laser induced breakdown spectroscopy", 《SPECTROCHIMICA ACTA PART B》 * |
| 彭飞飞等: "用激光点火辅助火花诱导击穿光谱技术实现铝合金的高灵敏元素分析", 《光谱学与光谱分析》 * |
Cited By (11)
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| CN105699359A (en) * | 2016-01-18 | 2016-06-22 | 大连理工大学 | Experimental device and method for obtaining annular uniform plasmas in barometric pressure air |
| CN106644407A (en) * | 2016-12-13 | 2017-05-10 | 西南技术物理研究所 | Laser-induced plasma ignition time measurement device |
| CN106644407B (en) * | 2016-12-13 | 2020-02-04 | 西南技术物理研究所 | Laser-induced plasma ignition time measuring device |
| CN107884128A (en) * | 2017-10-24 | 2018-04-06 | 中国航天空气动力技术研究院 | A kind of electro-arc heater water leakage fault diagnostic system based on atomic emission spectrum |
| CN108459012A (en) * | 2017-12-28 | 2018-08-28 | 中国科学院合肥物质科学研究院 | Portable laser plasma spark electric discharge component spectrum detecting system |
| CN112255149A (en) * | 2020-10-10 | 2021-01-22 | 中国科学院近代物理研究所 | Method and system for detecting particle size of loose particle accumulation and storage medium |
| CN112255149B (en) * | 2020-10-10 | 2022-07-05 | 中国科学院近代物理研究所 | Method and system for detecting particle size of loose particle accumulation and storage medium |
| CN113310968A (en) * | 2021-04-22 | 2021-08-27 | 清华大学 | Method for improving repeatability of laser-induced breakdown spectroscopy based on beam shaping |
| CN113310968B (en) * | 2021-04-22 | 2022-07-08 | 清华大学 | Method for improving repeatability of laser-induced breakdown spectroscopy based on beam shaping |
| CN114062348A (en) * | 2021-11-22 | 2022-02-18 | 清华大学 | Laser-induced breakdown spectroscopy detection system based on dielectric barrier discharge |
| CN114062348B (en) * | 2021-11-22 | 2023-09-12 | 清华大学 | Laser-induced breakdown spectroscopy detection system based on dielectric barrier discharge |
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